JPH0527559B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method of manufacturing a ceramic pen nib that improves ink ejection problems such as ink dripping and droplets.

(Prior art) For example, Utility Model Publication No. 42-19784, Publication No. 45-3700,
No. 48-44279, No. 49-24284, Special Publication No. 48-
As disclosed in various publications such as No. 35415, ink passages with porous ink passages are effective against ink discharge problems such as ink dripping and dripping caused by weak capillary force in the ink passages. .

(Problems to be solved by the invention) The above-mentioned ink ejection problems do not depend on the material;
Ceramic pen nibs with excellent abrasion resistance are no exception regardless of their shape, and as illustrated in Figs. 3 and 4, pen nibs made of ceramic have a tapered tip 2 that converges with the ink passage 1. In this case, the capillary force of the ink passage in the rear part may become a problem.

Therefore, making the ink passage porous is also effective for ceramic pen nibs, but because of the ceramic and the converging shape of the tip, there are various difficulties in actually making the ink passage porous. Accompany. For example, placing a porous material in the ink passage before sintering is subject to material constraints, and using a porous material such as a fiber bundle to make it porous after sintering is difficult. It is also important to try to
It may be difficult to position the porous material as desired. In addition, when the ink passage of the ceramic nib is made porous, consideration must be given to the resistance to dirt clogging of the porous ink passage.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a suitable method for manufacturing a ceramic pen nib as described above having a porous portion in an ink passage.

(Means for Solving the Problems) The present invention involves stretching and sintering a molded product of a ceramic material whose main ingredients are at least sintered powder and a shaping material, so that both the ink passage and the tip converge. In manufacturing a ceramic nib having a tapered tip, the molded product is combined with a ceramic material () which is the base material of the nib and has an ink passage;
The ceramic material () is present in the part of the ceramic material () that becomes the ink passage, and becomes the porous part of the ink passage after sintering treatment. The gist of the present invention is a method for manufacturing a ceramic pen nib, which is characterized by having a higher cutting property during stretching than that of the ceramic pen nib.

Among the materials to be prepared, first of all, as sintered powder,
Various aluminas such as α-, β-, γ-, silica,
Examples include various metal oxides, nitrides, carbides, borides, and fluorides, such as zirconia, barium titanate, silicon nitride, titanium carbide, clay minerals, and boron nitride, which undergo metamorphosis during the sintering process. Something like that would be fine. In addition, excipients include polyethylene, polypropylene, polybutadiene, polyisobutylene, polystyrene, nylon, polymethyl methacrylate, polyethyl methacrylate, poly-α-methylstyrene, polymetamethylstyrene, poly-α-deuterostyrene. , polyvinylidene fluoride, polyvinyl fluoride, polytetrafluoroethylene, acetate, silicone varnish, silicone rubber, butyl rubber, polyvinyl chloride, polyvinylidene chloride, chlorinated polyethylene, polyvinyl butyral, polyvinyl alcohol, carboxymethylcellulose, methylcellulose, polyvinyl Examples include various natural or synthetic resins and rubber-like materials such as acetate and polyvinyl ketone. You can use the following. In addition, other materials that may be used as needed include sintering aids such as magnesia, which is a type of sintering powder, and dimethyl Phthalate, diethyl phthalate, dibutyl phthalate, diheptyl phthalate, dioctyl phthalate, diethylhexyl phthalate,
Epoxidized soybean oil, dioctyl adipate, dioctyl azelaate, dioctyl sebacate, dibutyl sebacate, tricresyl phosphate, trioctyl phosphate, diethylene glycol dibenzoate, butylphthalyl butyl glycolate, polyethylene glycol, palmitic acid, stearic acid, etc. Examples include plasticizers, softeners, various solvents, and stabilizers.

Regarding the above-mentioned materials, at least the ceramic material () (base material of the pen nib with the ink passage)
It is preferable to use a sintered powder with a fine particle size. Tip convergence makes it possible to obtain fine handwriting, but if the particle size is large, it is difficult to achieve sufficient tip convergence.
It is desirable to have an average particle size of about 1 μm or less. In addition, as a shaping material for the ceramic material, it is preferable to select a material that can be easily plasticized so that it can be subjected to stretching treatment, which may be performed with heating in some cases, in order to achieve sufficient tip convergence. It is preferable to use a material that is difficult to cut, such as a crystalline thermoplastic resin. On the other hand, for ceramic material () (which becomes the porous part of the ink passage after sintering), it is better not to use sintered powder with a very small particle size, as it is easier to make the material porous. Essentially, it is sufficient to obtain a dispersion medium for the sintered powder. This is because the shaping itself can be done on the ceramic material (2) side, and it is not necessarily necessary to require sufficient stretching treatment on the ceramic material (2) side. Rather, it can be said that it is preferable from the viewpoint of dirt clogging resistance that the stretching treatment causes the ceramic material to become fragmented and a portion that is not made porous is formed at the tip of the pen tip. That is, the ceramic pen nib obtained by the present invention is one in which the ink passage exists as a hole through which the ink passage passes, or, as in the aforementioned pen nib A, the ink passage is formed in the outer wall at least at the tip of the pen nib. There are various types of grooves in the ink passage, but by dividing the ceramic material () at the tip of the pen tip, which is stretched the most during the stretching process, the porous part of the ink passage can be used for writing. Since it is located further away from the contact portion, it is less likely to become clogged with dirt.

A molded product is obtained using the above material, and subjected to stretching treatment, sintering treatment, and, if necessary, polishing, coloring, and other treatments to obtain a pen nib. In addition, considering that the ceramic material () and the molded product made of the ceramic material (2) will become longer due to the stretching process, a recess is formed on the surface of the molded product of the ceramic material (2), and the ceramic material (2) is inserted into this recess. Although a method such as filling the material (2) may be adopted, it would be easier to use an extrusion molding method called coextrusion or composite extrusion. It is also easy to make the cross-sectional shape as appropriate, including when it is desired to have a plurality of ink passages. In addition, ceramic materials ()
It is not necessary that the porous portion occupies the entire area of the ink passage in a suitable cross section; on the contrary, it may be formed outside the ink passage.

(Example) Hereinafter, parts simply refer to parts by weight.

<Example 1> α-Alumina for ceramic materials (average particle size: approx. 0.5 μm, maximum particle size: approx.
3μm) 100 parts magnesia (average particle size approx. 1.3μm, maximum particle size approx.
5 μm) 0.3 parts Polyvinyl chloride 15 parts Dioctyl phthalate 10 parts Stearic acid 2 parts The above blended materials were sufficiently kneaded in a heating kneader and then pelletized.

α-alumina for ceramic materials (average particle size approx. 3.0 μm, maximum particle size approx.
18μm) 60 parts magnesia (average particle size approx. 1.3μm, maximum particle size approx.
5μm) 0.3 parts graphite (pore forming material) (average particle size approx. 60μm, maximum particle size approx. 120μm) 40 parts polyvinyl chloride 15 parts dioctyl phthalate 7 parts After thoroughly kneading the above blended materials in a heating kneader, pellet It became.

Using both of the above pellets, an integrated molded product (rod-shaped object with a diameter of approximately 3.2 mm) of ceramic material () and ceramic material () is produced using an extruder equipped with a composite die.
I got it.

This rod-shaped object was rotated about 1 time/second and exposed to hot air (using a commercially available hair dryer) with a width of about 7 mm and a center temperature of about 130°C for about 7 seconds, and then stretched at a speed of about 5 cm/second to lengthen it. Maximum temperature after adjusting to 20mm
Sintering treatment was performed at 1600℃ (air atmosphere).

After cooling, I took it out and found the attached figures 1 and 2.
The maximum diameter of the shape as shown in the figure is approximately 2.6 mm and the length is approximately 16.5 mm.
A pen nib was obtained by polishing the tip with sandpaper, giving it a gloss with a barrel, and cutting it to a length of 5 mm. still,
The reference numbers in FIGS. 1 and 2 are: 3 indicates the porous part of the ceramic material (), 4 indicates the non-porous part of the ink passage formed by dividing the ceramic material () during the stretching process, and others. are made to match those in FIGS. 3 and 4 described above.

<Comparative Example 1> Everything was the same as in Example 1 except that 15 parts of polyvinyl chloride used for preparing the ceramic material () in Example 1 was changed to 18 parts, and 7 parts of dioctyl phthalate was changed to 9 parts. I did the same thing. The obtained product is almost the same as that obtained in Example 1, except that the non-porous part 4 of the ink passage in FIG. 1 was not present and the porous part 3 was present up to the tip.

(Effect of the invention) When we assembled the products obtained in Example 1 and Comparative Example 1 into a writing instrument and examined their ink ejection properties as pen nibs, we found that both of them were good enough that there was no need to consider the problems of ink dripping or droplets. It had However, the material obtained in Comparative Example 1 was more likely to have dust attached than the material obtained in Example 1. As described above, according to the present invention, the ceramic pen nib has a tapered tip that converges with the ink passage, and the ink passage has a porous portion, but the tip has a porous portion. Since it is possible to obtain a pen having no ink passage, it is possible to obtain a ceramic pen nib which has excellent ink ejection performance and dust clogging resistance. Also, it can be produced extremely efficiently because it can be obtained by stretching and sintering a molded product made of the ceramic material (2) and the ceramic material (2).

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view of essential parts showing an example of a ceramic pen nib obtained by the present invention, and FIG.
FIG. 3 is a longitudinal sectional view of a main part showing an example of a ceramic pen nib, and FIG. 4 is a cross sectional view taken along the line A--I of FIG. 3. A... Ceramic pen nib, 1... Ink passage, 2... Tapered tip, 3... Porous part, 4
...Non-porous part.

Claims (1)

[Claims] 1. A ceramic pen nib having a tapered tip that converges with the ink passage is produced by subjecting a molded ceramic material mainly composed of sintered powder and excipient material to stretching and sintering. In doing so, the molded article is made of a ceramic material () which is the base material of the pen nib having an ink passage, and a portion of the ceramic material () which is the ink passage, and after sintering, the porous part of the ink passage is removed. A method for manufacturing a ceramic pen nib, characterized in that the ceramic material () has a higher cutting property during stretching than the ceramic material (). .